They only express the number of balls required for the pattern with specific brands of wool, but I was wondering if anyone would know or give me examples of how many grams and yards would be required using various types of yarn? I do have left over balls as follows, but not sure if it would be enough:

x3 50g (super fine 1 kroy socks 75 wool 25 nylon)

x1 100g (medium 4 pure wool)

x3 50g- 130yds 50% cotton -50% acrylic

As you get experienced, can you actually guess how many balls are required for patterns that are not clear how much you need based on the pattern? I know you can calculate based on the number of stitches or inches required, but math was never my strong point - would that make me a terrible knitter? Thank you so much!!

I usually look the yarn up either on Ravelry or a commercial site like Webs to find out yardage and also the given gauge. I tend to buy yarn generously because I'd rather have leftovers than come up short.
There are various yarn calculators around like this one that can help at least approximate total yardage.http://www.jimmybeanswool.com/secure...Calculator.asp